1. Field of the Invention
The present invention relates to a storage control technology for data backup and/or restoration.
2. Description of the Related Art
For example, Japanese Patent Application Laid-open No. 2002-41345 discloses a storage control method for connecting a computer, a disk storage, and a tape library device to a communication network called SAN (Storage Space Network) and performing backup of data stored in the disk storage to a tape library device with a server (referred to hereinbelow as a backup server) for backup processing.
With the above-described storage control method, data that are the backup object are backed up via a backup server. For this reason, the backup performance depends on the backup server, and when the processing performance of the backup server is poor, the time required for the backup increases.
Furthermore, a tape medium (simply referred to hereinbelow as “a tape”) is apparently effectively as a backup destination of data. This is because a bit cost (cost per 1 bit) is lower than that of a disk device (for example, a hard disk). However, a tape often requires more time to read and write than a disk device. An especially long time is required in the case where the so-called random access is generated.
A similar problem also arises, for example, when the backed-up data are restored in a sequence inverted with respect to that of the backup, more specifically, in the case where the data are restored from the tape library device to the disk storage via the backup server.